Methylcellulose Oil Paint Medium

January 4, 2011

Awhile back I mentioned how I was using methylcellulose (“MC”) as a water/oil emulsion to make undertones for oil paintings. I thought I’d go into that in more detail here. This mixture is taken from recipes that use egg yolk and oil in the same way. The benefit of this medium is it accelerates the painting process. The MC will cause the oil to set up more rapidly. I prefer it to just using diluted paint, and it can be diluted with just water instead of using spirits (mineral or gum turpentine.)

1: This shows the MC in gel form. The MC powder can be gelled by merely adding water (1 part powder, 8 parts water.) The water I’m using here is distilled, by the way. I let this sit for a few hours to gel properly. The dry powder will not spoil, but I have seen mold form in the gel after several months, so I don’t make too much gel ahead of time. You could add a preservative, such as a drop or two of clove oil or thymol, to extend the storage time, if you wanted. After you add the oil (as I show later) it should last indefinitely without needing a preservative.

3: The diluted MC has been mixed with 2 teaspoons refined linseed oil. I add the oil slowly while stirring, like making mayonnaise. Notice that the emulsion causes the mixture to become opaque. It will dry clear.
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4: Here I’m making a quick paint on a small marble slab using the above medium and a premixed light gray pigment (titanium white and ivory black.) I drop ¼ teaspoon of the medium into a single teaspoon of dry pigment and fold it into the center, mixing with a paint knife.
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5: I’ve added another ¼ teaspoon of medium and kept mixing for a few minutes until it’s all combined into a nice thick paint. Notice how much darker in value the paint is than the original dry powder. It will stay at this value even after it dries. The paint will have a matte sheen when dry.

6: Here I’m showing a few other paints I’ve mixed together in the same way: titanium white, cerulean blue and dioxazine violet. No mulling or grinding was required for any of these, just thorough mixing with a knife for a couple minutes to make a smooth paint. These colors will all be mixed with the gray paint for my undertones.
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Notes:
Always use care when handling pigments since some of them can be hazardous. You can also use this medium with oil paint without having to make your own from dry powder, just remember that you’d be adding oil so it will be a “fatter” layer. Alternatively, you could make your commercial paint leaner by mixing it with just diluted MC (step 2 above) and not adding extra oil. Be sure it’s well mixed before using.

This paint medium tends to cake up some if applied too thickly, another reason why I tend to use it only for thin undertones, but it is possible to complete a whole painting with this paint mixture. The top layers should not be thinned (fat over lean.) Because it sets up rapidly I can start the next layer of painting after waiting only a few minutes. If it’s been further diluted with water it dries even faster. I’ve found a few drops of glycerin can help make the paint handle more smoothly.

Another benefit to using MC is for cleaning up. Because it’s water and oil soluble you can use the gel as you would soap; although, I’d still recommend using soap after wards. First wipe paint from your brushes on a rag, then rub in some MC gel, and finish with soap and water. Some painters recommend cleaning the brush with oil, even cooking oil, prior to washing with soap and water. This works just as well to remove most of the remaining paint, and washes out more easily.

I’ve also used carboxy-methylcellulose (“CMC”) instead of MC. It reportedly has stronger adhesive properties, but has a slight amber color to it when in gel form and doesn’t seem quite as smooth as MC, at least from what I’ve used. Otherwise I’ve not noticed a difference.

A web search will give you several sources for MC or CMC powder online. MC is used for bookbinding, and CMC is used with ceramic glazes. A recent purchase of CMC cost me @ $12 USD for a 1 pound bag. Lineco sells MC in small containers that you can find at Dick Blick. A little bit goes a long way. Studio Products sells a premixed CMC solution called “amber gum.”

In the first step above I show how the gel is made by just adding water, 1:8. I’ve found that CMC powder tends to make a thicker gel than MC, so you may wish to use more water, or it can be thinned after it gels.

Please note that The Studio Products company is no longer in business so that link mentioned at the bottom of this article is dead. I don’t know any other company that makes a pre-mixed CMC medium but you could easily do so from dry powder.

Search pigment store sites Kremer or Earth Pigments, art conservation supply stores, bookbinding supplies, etc. Sennelier sells it, or there’s “MethoCel” from Dow. A little will go a long way. I have an 8oz jar that I’m still working my way through several years later.

I wouldn’t say I favor it over other mediums or methods. Egg & oil also works well in the same fashion, and for undertones I have a selection of different mediums to choose from just to keep things interesting. Shellac or acrylic based inks, for example, is another option for undertones, and they would dry much faster. I like this mainly because it’s easy, effective, and cheap to use.

I’ve had no adhesion problems with MC & oil medium as long as I don’t dilute it too much. If I use it as a medium with oil paint I also don’t dilute it and keep the amount low, about 10% or so by volume. This is a water and oil emulsion, so when you mix it with paint it’s important to stir it up on the palette well before applying it to the surface. Don’t just dip your brush into it the way some artists do with mediums. Once you stir it up it stays mixed for a long time, as does egg yolk.

Yes, egg & oil paint is safe to use on an oil ground. Anything oil mediums will adhere to this will also.

[…] made the methylcellulose gel using Lineco MC, with a recipe from D.B. Clemons at https://dbclemons.wordpress.com/2011/01/04/methylcellulose-oil-paint-medium/. It was extremely easy and perhaps could be made easier by just increasing the water in the first […]

[…] and Carboxymethyl cellulose (CMC) as art mediums before, but not in this manner. (Here’s a link to a previous post using MC mixed with oils.) I’ve made gesso before using rabbit skin glue or casein for many […]